public class Test23 {
    public int numberOfArithmeticSlices(int[] nums) {
        int n = nums.length;
        int dp[] = new int[n];
        int count = 0;
        for(int i = 2;i < n;i++) {
            if(nums[i] - nums[i - 1] == nums[i - 1] - nums[i - 2]) {
                dp[i] = dp[i - 1] + 1;
            }
            count += dp[i];
        }
        return count;
    }
}
